Modular timepieces are known. Although very widely known in electronic horology, they are less frequent in mechanical horology, where construction in modules, generally devised to break down the same basic movement into several calibres with different functions or having a different presentation, is usually more expensive than the traditional method of manufacture. Only a few additional mechanisms, made on additional plates, are relatively widespread.
Modular construction conventionally imposes the constraint of machining high precision interfaces, because of the accumulation of assembly clearances between modules, which require very tight tolerances for each module, to ensure a satisfactory result for the entire unit.
Manufacture in modules is also very often detrimental to the total thickness of the movement, and it is difficult to make ultra flat or even simply flat movements.
However, modular construction remains an interesting objective for timepiece manufacturers, since it allows assembling tasks to be split. In return for the tighter manufacturing tolerances required by the accumulation of clearances between modules, the final assembly operation can be carried out by less skilled personnel because it is less complicated. However, the final assembly operation still requires the knowledge and sensitivity of a watchmaker.
EP Patent Application No. 1 079 284 in the name of ETA discloses a watch with two main modules each of which contains half of the components.
EP Patent Application No. 0 862 098 in the name of VOSS discloses a modular watch with a timing mechanism forming an entire module.
EP Patent Application No 1 211 578 in the name of ETA discloses an ultra thin electromechanical movement with stacked modules, implementing tubular elements compensating for the variations in thickness of the assembly elements.
WO Patent Application No. 2009/056498 A1 in the name of JOUVENOT FREDERIC discloses an additional self winding mechanism wherein the veil of the oscillating weight is mounted between the main set of hands on the one hand, and the chronograph and off-centre seconds hands on the other. This additional mechanism is not a module, since it is sandwiched between the components of the main movement, and various arbours and pipes of the movement pass through it.
CH Patent Application No. 647 125 A3 in the name of DUBOIS & DEPRAZ SA discloses a chronograph with a motor module, which includes a first power take-off integral with the cannon-pinion thereof and a second power take-off integral with the seconds arbour. A chronograph module is removably mounted and the gear train thereof is driven by the second power take-off. The two power take-offs are concentric and accessible from the same side of the motor module. The chronograph module is secured between the dial and the top face of the motor module. The hands form part of the chronograph module.
US Patent Application No. 2008/112 273 A1 in the name of PELLATON LOÏC (ETA SA) discloses a movement with a fixed support fitted with a display module comprising a central bar secured to the support and an annular display member which rotates freely about the central bar, abutting on the fixed support. The display member has a contact surface. The central bar includes three positioning surfaces formed by three protruding portions cooperating with said contact surface to position the display member axially on the fixed support. The central bar includes three assembling surfaces which are axially and angularly shifted relative to the positioning surfaces. The display member has three lugs. The contact surface, the positioning surfaces, the assembling surfaces and the lugs are arranged to form together a bayonet assembly system for mounting the display member on the bar.
US Patent Application No. 2011/110 199 A1 in the name of GIRARDIN FREDERIC discloses a module for actuating one element of a movement, intended to be mounted on a movement frame. This module contains a mechanism comprising a pivoting control stem moving between axial positions, a control pinion rotatably integral with the control stem, and at least one actuation member arranged to cooperate with the control pinion in one of the axial positions of the stem. The control pinion is integral in translation with the stem when the latter moves from one axial position to another. The module comprises an independent case containing the mechanism, and a connecting means which comes out of the case and is arranged to kinematically connect the actuating member to the element of the movement to be actuated, so that the actuating member can actuate said element regardless of the position of the module on the movement frame.